Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5a3760b27602a1b…

MALICIOUS

PDF

71.0 KB Created: 2021-09-19 14:09:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c9b91c7fe51a5bb6ed7febfd5206a248 SHA-1: 5c94367990b9b61b611502fe54544dcc74b1428a SHA-256: a5a3760b27602a1bc7f089034bba6751ed5d4d72d393de965b0f5ceb03cbbe0d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://allytemp.ru/uplcv?utm_term=cast+iptv+from+iphone+to+chromecast
    • http://hanhthien.net/uploads/file/16088582322.pdf
    • http://icloudcleaners.com/uploads/account/autoresponderfiles/gamoxokorudofelive.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140f09c1db66---pisabevonotom.pdf
    • http://janjoling.com/public/ckfinder/userfiles/files/xuxebugadikajadim.pdf
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/81043d67a059338fc87d5120e69f8f3b/jafifiwojevijid.pdf
    • http://3e-machinery.ru/app/webroot/filesfiles/xunisixo.pdf
    • https://bhsbeacon.com/FCKeditor/file/mebowowidevop.pdf
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/bf5694776a51cfc65d915d5f4f5f0d80/75596383511.pdf
    • http://nguyenthaotech.com/upload/files/fevarikubikopo.pdf
    • http://altiro.nl/home/tjerk/file/21887357815.pdf
    • http://tottazo.com/userfiles/file/92097701656.pdf
    • https://cvconstructionsgoa.com/pharma/admin/userfiles/file/kabunowidagonovut.pdf
    • https://ispartaprefabrik.com/ckfinder/upload/files/3984341789.pdf
    • http://congtrinhnhaviet.vn/upload/files/sikili.pdf
    • https://rosycaffe.com/file/43711250627.pdf
    • http://ecohort.com/userfiles/files/nibisotumugogiv.pdf
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/89032772895.pdf
    • http://studioaba.net/userfiles/files/vuwoxelixakikadibavib.pdf
    • http://metall-press.ru/files/pibomavelilon.pdf
    • http://interfacetravels.com/app/webroot/js/ckfinder/userfiles/files/22634373246.pdf
    • http://idevicesplus.nl/app/webroot/files/userfiles/files/98708724808.pdf
    • https://bizimpin.com/calisma2/files/uploads/tujivumejopejovam.pdf
    • http://toyotaquangninh.org/data/dulieu/files/93129684437.pdf
    • http://ihdbd.org/upload/files/12567632675.pdf
    • http://spbmedaks.ru/sites/default/files/uploads/3859547533.pdf
    • http://perila-vrn.ru/userfiles/file/12460618554.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b696.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB696 16792 bytes
font_01_sfnt_off0000cead.bin
78e61d1f968909cc4e5691a242f5aa98cdc0bd8cc78618806eca159060686da5
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEAD 10796 bytes
font_02_sfnt_off0000e76c.bin
c47773044b309011b6b0a4c79ef3055b0245d361cc9976c883781b41066ffb7d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE76C 15096 bytes